Lymphangiolipoma of the thoracic spine in a pediatric patient with Proteus syndrome.

Proteus syndrome is a rare hamartomatous disorder involving macrodactyly, hemihypertrophy, and subcutaneous lymphangiomas; fewer than 25 cases have been reported worldwide. We report a case of a thoracic epidural lymphangiolipoma in a 5-year-old boy with Proteus syndrome. Computerized axial tomography (CT) of the thoracic spine revealed a left posterior mediastinal mass that extended into the spinal canal through adjacent neural foramina. No sign of spinal cord compression was observed despite the extensive volume of tumor within the spinal canal. Surgical debulking utilizing a T3-10 laminectomy resulted in gross total resection of the tumor. Microscopic examination of the surgical specimen revealed a lymphangiolipoma. No previous report of spinal cord involvement has been reported in this syndrome. A detailed discussion of the phenotypic features and probable mode of genetic transmission is included.